Recent research into the cost of various medical procedures has shown the impact of certain complications encountered in surgery on the total cost of a patient's stay in the hospital. The researchers used regression analysis and found the following results: Total cost for patient Constant, plus ax Length of stay (measured in days), plus bx Presence of one or more complications 1 if true, O if false), plus cx Use of a laparoscope (-1 if true, 0 if false) where a, b, c are coefficients of the regression model. The laparoscope is an instrument somewhat like a miniature telescope with a fiber-optic system that brings light into the abdomen. It is about as big around as a fountain pen and twice as long. The research, based on 62 patients, showed the following regression results R-squared: 54% Constant term: $3,860 Coefficients and t-values for independent variables Length of Stay Complications Laparoscope s 632 Coefficient t-value $1,931 5.01 919 3.02 9.22 Required: 1. What is the estimated cost for a patient whose surgery has complications and who stays in the hospital 2 days, and whose surgery requires a laparoscope? Estimated cost 2. Which, if any, dummy variables are used in this regression? (You may select more than one answer. Single click the box with the question mark to produce a check mark for a correct answer and double click the box with the question mark to empty the box for a wrong answer. Any boxes left with a question mark will be automatically graded as incorrect.) Use of a laparoscope Length of stay (measured in days) Complications were present